(The above is a sketch I did of game-Blue and two of her Pokemon: Milotic and Pikachu. Its currently hanging in my little cousin's hospital room, where they can watch over him as he gets better.)
As we rejoin Blue in her journey to be the very best that no one ever was, Blue has wandered into the mysterious world known as the Battle Frontier. The Battle Frontier does not actually exist in the same world as the rest of Pokemon, clearly, as the rules here are incredibly strange. For example, Blue's Pokemon could not actually follow her around as they did everywhere else*. There's no money, just a weird sort of currency known as "BP". Also, when engaged in battle, Blue had to follow the often ridiculous rules set by the local warlords, known as Frontier Brains. A goofier name for some of the strongest trainers in the world, Blue could not imagine. Seriously "Brain"? Anyway, through magic or some other power, the Brains could set up any kind of ridiculous rule that they wanted for their Gyms.
The first things seriously annoying about the Frontier was how you couldn't just go up and fight the Frontier Brains. Instead, you had to fight three streaks of seven battles consecutively, with the only only breaks coming after a streak was completed. Only after this complicated ordeal, the end of the third streak (the twenty-first battle) did Blue even have a shot at fighting the Brains. Lose once, and you're back to the beginning. And above all that, Blue had to follow whatever crazy local battle rules the Brain had set up for the Gym. Luckily they usually heal your Pokemon between fights, so it really isn't so hard as it might sound. But the real problem is that Blue couldn't fight at full strength. She had to follow whatever strange restrictions the Brains set up: be it only three Pokemon, one Pokemon, or in the worst case scenario, rented Pokemon.